Design of nearly perfect reconstructed non-uniform filter bank by constrained equiripple FIR technique

In this paper, an efficient iterative algorithm is proposed for the design of multi-channel nearly perfect reconstructed non-uniform filter bank. The method employs the constrained equiripple FIR technique to design the prototype filter for filter banks with novelty of exploiting a new perfect reconstruction condition of the non-uniform filter banks instead of using complex objective functions. In the proposed algorithm, passband edge frequency (ωp) is optimized using linear optimization technique such that the filter coefficients values at quadrature frequency are approximately equal to 0.707. Several design examples are included to illustrate the efficacy of this methodology for designing non-uniform filter bank (NUFB). It was found that the proposed methodology performs better as compared to earlier reported results in terms of reconstruction error (RE), number of iteration (NOI) and computation time (CPU time). The proposed algorithm is very simple, linear in nature, and easy to implement.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An efficient iterative algorithm is proposed for the design of nonuniform filter bank. ► A new perfect reconstruction of a prototype filter of filter bank is developed. ► A prototype filter of nonuniform filter bank is designed by constrained equiripple FIR technique with exploiting a new perfect reconstruction condition. ► In the proposed algorithm, passband edge frequency is optimized using linear optimization technique such that the filter coefficients values at quadrature frequency are approximately equal to 0.707.